Magnetic fishing tool



Sept. 12, 1950 J. D. NOBLE 2,522,294

MAGNETIC FISHING TOOL Fiied Sept. 13, 1949 FIG.3

Patented Sept. 12, 1950 UNITED STATES PATENT OFFICE MAGNETIC FISHING TOOL John D. Noble, Kermit, Tex.

Application September 13, 1949, Serial No. 115,511;

4 Claims. (01. 294-4555,)

This invention relates to improvements in fishing tools for wells; the object of the improvem nts is o Provide a simplified. fishing tool which will operate in conjunction with either a drilling stem, on a cable tool rig, or, in a drill collar on a rotary drilling rig.

This invention has particular utility when attached to a rotary drilling rig which will enable the fishing tool to reach the object to be removed (usually a broken part or segment ofa bit on a drill) even though said object be beneath the temporary bottom of the well. This is accomplishcd by a water-tight unit containing a battery, composed of either Wet cells or dry cells, connected series parallel, to the particular magnetic strength required, said sealed unit being contained within an elongated protective case, which tapers and attaches, at the top end, to the drill collar (or drilling stem, when used in a cable tool rig) and at the lower or open end con" tains a detachable milling end, thereby permit ting the magnetic internal part of this fishing tool to reach through any sediment or cave in and attach to the object to be extricated by means of a modified redrilling of the Well with the added use of circulating water flowing.

through the drill pipe and between the walls of the protective case and the magnetic watertight unit.

Referring to the drawings:

Fig. 1 is a fragmentary view of a drilling rig in position with the fishing tool of the invention herein connected thereto.

Fig. 2 is a detail of the connection of the tool to a. drill collar.

Fig. 3 is an enlarged, cross-sectional view, with parts cut away, of the assembled "tool, showing the external protective case with its tapered screw connection to the drill collar (or drill stem) the milling end; and the enclosed water tight magnetic unit with its sliding connection to the said external case, shown at maximum elevated position and with part cut away from said enclosed magnetic unit to show internal mechanism.

Fig. 4 is a direct internal right angular view of winding on steel core, and connections, numbered to correspond to same sections on Fig. 3.

A drilling rig derrick l is shown having power for drilling operation supplied by motor 2. Drilling pipe 3 extends through rotary table 4, into well 5 containing a drill collar 6 at its lower extremity, said drill collar having a, tapered threaded opening in its lower end with an opening to permit circulation of water from pump 1 through hose 8 and thence down througn cure of drill pipe into the tool connected to drill collar 6 in place of a bit.

The tool is herein shown, consists of two main operating parts:

The external protective and drilling unit AA, and

The internal sealed magnetic unit BB.

Th external protective unit consists of three detachable parts, comprising the tapered top section 9, which has a threaded hollow pin II which connects to the drill collar 6 or drill stem (not illustrated), whichever the case may be, and allows the flow, or circulation of water through opening I5 (when used with a drill collar). Section Battaches by means of threads to section ID at point IS on Fig. 3.

Section I 0 consisting of a steel hollow tube connection to section 9 as per above, and contains a steel disk 12 welded to the inside of section ill at H. Disk [2 provides the support for the internal sealed magnetic unit BB hereinafter described. Said disk 12 contains six, more or less, holes or openings l4 topermit the circulation of water entering the tool at l5. At the exact center of said disk I2 is a solitary hole It! through. which passes the rod I9. Hole I8 is milled large enough to permit rod 19 to slide freely there through. Section Ill attaches by means of threads to section II at point 20 of Fig. 3.

Section I l is a milling end connected to s c i n was per abov and contains teeth 2| used to dig through a cave-in or other sediment covering the object to be removed by means of rotary action and circulating water (when used on a rotaryrig). Section II also is used as a pro tection to the bottom or lower part of the internal sealed magnetic unit BB. When the entire tool is being lowered into the well, and before any external object or substance contacts the internal sealed magnetic unit BB, the lower extremities of BB are flush, or even with, the lower extremities of AA or 2!.

The internal sealed magnetic unit BB consists of a steel tube which tapers to rod 19 which rod l5 fits through hole 63 on disk I! which in turn is welded to the external unit AA. Rod I 9 is threaded at its extremity 24, at which are screwed two locking nuts 25 and 25. Nut 26 being the lower of the two nuts, when the tool is in operating position, rests upon disk I2 and thereby provides the support for the entire internal sealed magnetic unit BB at l8. When 26 is resting against disk I 2 the internal sealed magnetic unit BB is at its maximum lowered position heretofore referred to. At maximum elevation of BB, stopring 23 rests against the lower surface of disk l2 and thereby prevents BB from raising to the point where the expanding portion of rod 19 might possibly cause the internal unit BB to become stuck in hole [8.

At stopring 23 rod l9 expands into the hollow tube section of BB 21. Section 21 attaches to section 28 at 29 by means of threads to make a watertight seam. Section 21 unscrews from section 28 to enable the operator of the tool to have access to two switches 30 and 3| set in a fiber disk 32. Disk 32 is milled to fit a slot or insert just below the connecting point 29 which connects 21 to 28.

Switches 38 and 3i control the flow of electric current stored in the batteries 33 (either wet cells or dry cellsconnected series parallel), when said electric current is fiowing it sets up magnetic fiux beneath fiber disk 3 being the grasping section of the tool. Section 28 attaches to section 38 by means of threads forming a water tight seam.

' Section 38 is the lower extension of the steel tube of section 28. Said steel tube fits within the outer protective unit tube AA with approximately inch of space 39 between the walls of the two tubes to allow for the circulation of water entering the tool through opening I5. At point 40 just below the seam 37 is Welded steel disk 35 which acts as support for batteries 33 and a water tight seal to area 35 and the space above disk 32. Above and directly below disk 36, in the exact center of said disk, are two water tight nuts 4! and 42 on Fig. 4 which hold steel rod 43 separate steel disk 36 from fiber disk 4 Fiber disk 44 and fiber disk 3- 5 act as spool ends to winding 45 on rod 13. Nut 46 holds disk 34. 'Winding d5 connects with batteries 33 and switches 30 and 3! by connecting wires running through water tight packing-boxes 4-1.

Tool is set in operation by manually throwing switches 39 and 31 sealing BB at 29, inserting rod 19 through hole IS in disk [2, attaching nuts 25 and 26 sealing AA at 16, connecting tool to drill collar, or drill stem, depending upon the type of rigging in use, and finally in lowering the tool into the well.

The electromagnetic fishing tool herein is a self-contained unit, conforming to drilling re-' quirements, and can be substituted for a bit on either a rotary rig or a cable tool rig to remove by magnetic action, cones, bearing, bits or parts thereof, and other magnetizable objects of relative similar size.

The electromagnetic fishing tool herein is of particular utility in its ability to engage magnetizable objects which are resting beneath sediment or a cave-in. This is accomplished when the tool is employed on a rotary rig thereby enabling the pick up face to contact said buried objects by use of the revolving cutting action of the milling end of the tool in conjunction with the use of circulating water pumped through the tool to said milling end.

What is claimed and it is desired to secure by Letters Patent is:

1. An electromagnetic fishing tool, comprising an electromagnetic unit contained within an outer casing, said casing terminating in a rotary milling end, means connected to the outer casing, means connected to the electromagnetic unit, the connection between the casing means and electromagnetic means allowing rotatable and limited slidable movements of the said electromagnetic unit within the said outer casing, said connecting means permitting the electromagnetic unit to remain in contact with and ride on the material at the bottom of the well when the rotary milling end is in cutting position and operation.

2. An electromagnetic fishing tool as in claim 1, said outer casing having means at its upper end for connection with a drilling stem, said means including a passage for washing fluid from the drilling stem, the connection of the electromagnetic unit and the outer casing allowing the flow of the washing fluid to the said millin cutters.

3. An electromagnetic fishing tool as in claim 1, said connection between the electromagnetic unit and the said outer casing comprising a disc fixed into the outer casing at the upper end thereof and having a central aperture and apertures for the passage of washing fluid, a rod mounted in said central aperture for rotative and limited slidable movement, said electromagnetic unit being rigidly connected to and suspended from said rod.

4. An electromagnetic fishing tool as in claim 1, said electromagnetic unit comprising a watertight casing in which are mounted an electromagnet, and source of current connected thereto.

JOHN D. NOBLE.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,589,678 Bornemann June 22, 1926 1,611,831 Gates Dec. 21, 1926 

